Post-Fukushima radiation education for public health nursing students: a case study.

BACKGROUND: The recent Fukushima Nuclear Power Plant accident was one of more than 200 serious nuclear/radiation incidents (accidents and disasters) that occurred worldwide since 1945. The current Fukushima disaster is in the recovery phase with the decreasing levels of radiation in the environment. However, fears and stigma related to the perceived risk of radiation exposure persist among the general population. INTRODUCTION: To improve on students' preparedness for social and public health challenges after a radiation incidence, radiation education was provided for undergraduate public health nursing students. AIM: This case study reports the development and implementation of the first class of radiation education in public health nursing, as well as students' reflections on their class experience. METHODS: We included a 90-min radiation class in an undergraduate public health nursing course in Tokyo, Japan. Lectures/discussion on technical and environmental aspects provided the minimally essential content for basic radiation knowledge. After class, all the 65 students were invited to freely write their reflections on the class. With their consent, 61 students' anonymous written accounts were qualitatively analysed. RESULTS: Five themes emerged: awareness of ignorance about radiation, problems produced by the mass media, becoming knowledgeable about radiation, public health nurses' role, and trustful and enjoyable lecture. DISCUSSION: The class inspired students to consider social, psychological and relational aspects of knowing and not knowing about radiation and their future professional role. CONCLUSION AND IMPLICATIONS FOR NURSING: Once radiation is taught at school, nursing students will emerge as professionals with the belief that radiation is within their professional purview. Education is key to disaster prevention, preparation, response and recovery. Given the ubiquitous nature of health challenges after a radiation incident, radiation education is indispensable for nursing students worldwide.

CD146 is a novel marker for highly tumorigenic cells and a potential therapeutic target in malignant rhabdoid tumor.

Malignant rhabdoid tumor (MRT) is a rare, highly aggressive pediatric malignancy that primarily develops during infancy and early childhood. Despite the existing standard of intensive multimodal therapy, the prognosis of patients with MRT is dismal; therefore, a greater understanding of the biology of this disease is required to establish novel therapies. In this study, we identified a highly tumorigenic sub-population in MRT, based on the expression of CD146 (also known as melanoma cell adhesion molecule), a cell adhesion molecule expressed by neural crest cells and various derivatives. CD146+ cells isolated from four MRT cell lines by cell sorting exhibited enhanced self-renewal and invasive potential in vitro. In a xenograft model using immunodeficient NOD/Shi-scid IL-2Rγ-null mice, purified CD146+ cells obtained from MRT cell lines or a primary tumor exhibited the exclusive ability to form tumors in vivo. Blocking of CD146-related mechanisms, either by short hairpin RNA knockdown or treatment with a polyclonal antibody against CD146, effectively suppressed tumor growth of MRT cells both in vitro and in vivo via induction of apoptosis by inactivating Akt. Furthermore, CD146 positivity in immunohistological analysis of 11 MRT patient samples was associated with poor patient outcomes. These results suggest that CD146 defines a distinct sub-population in MRT with high tumorigenic capacity and that this marker represents a promising therapeutic target.

Some epidemiological aspects of Toxoplasma infections in a population of farmers in Japan.

A total of 3606 serum samples collected from a population of farmers in Japan, were examined for antibodies to Toxoplasma by enzyme-linked immunosorbent assay, to study prevalence and possible transmission route(s). The prevalence of antibodies gradually increased with age and was significantly higher in males (28.8%) than in females (16.3%; P less than 0.001). Irrespective of age and sex, however, mean antibody levels for two distinct groups quantitatively separated on frequency distribution were almost constant. While seropositivity did not differ in people with and without cat contact, consumption of raw meat was significantly correlated with antibody prevalence. The difference in prevalence was partly explained by greater raw meat ingestion by males (41.6%) than by females (17.2%; P less than 0.001). Beef, chicken, horseflesh, whale meat, wild boar and venison were the sources of raw meat.

A novel proteinase, glucagon-degrading enzyme, secreted by a human pancreatic cancer cell line, HPC-YO.

Sixty-four kinds of cell lines were examined as to their ability to degrade glucagon using conditioned-media obtained from their protein-free cultures. Two human tumor cell lines were shown to produce this activity, and the cell line, HPC-YO, established from a human pancreatic carcinoma was shown to produce the highest level of activity. The glucagon-degrading enzyme (GDE) was purified from HPC-YO conditioned-medium by a combination of ion-exchange, gel filtration, and hydroxylapatite column chromatographies. The purified GDE also degraded vasoactive intestinal polypeptide (VIP) and secretin, however, it did not cleave EGF, gastrin, insulin, somatostatin, substance P, neurotensin, or growth hormone. The molecular weight of GDE is 83,000, as determined on SDS-polyacrylamide gel electrophoresis. The N-terminal amino acid sequence of GDE was blocked, and the five partial amino acid sequences obtained on lysyl-endopeptidase digestion were determined to be N-L-T-E-E-Y-D-V-S-D-G-E-I-E-L-L-Y-E-K, V-E-T-Y-Y-D-L-L-F-E-K, L-Y-W-F-L-D-E-A-K, S-N-S-T-S-Y-V-K, and Y-Y-A-S-T-S-Y-D-D-T-Y-K. The same or homologous amino acid sequences have not been found in known proteins, demonstrating that GDE is a novel peptidase that degrades the secretin family: glucagon, VIP, and secretin.

Dengue hemorrhagic fever in Jakarta, Indonesia in 1988: isolation of dengue virus from patient whole blood using cell cultures.

During an outbreak of dengue hemorrhagic fever (DHF) in Jakarta, Indonesia in 1988, we attempted to isolate dengue virus using mosquito cells and a medium containing heparin. Whole blood, immediately after being drawn from patients, was inoculated into Aedes albopictus cell cultures temporarily maintained in the heparin-containing medium. The overall virus isolation rate was 25% (17 of 69) samples collected within three days after admission of the patients to hospital. No virus was obtained thereafter. The successful virus isolation was apparently not related to titers of anti-dengue virus hemagglutination-inhibiting antibodies present in patients' sera. The viruses were recovered from cases of each of the four World Health Organization grades of DHF without significant differences. The technique is simple and easily performed at bedside.

Detection of Plasmodium vivax and Plasmodium falciparum circumsporozoite antigen in anopheline mosquitoes collected in southern Thailand.

During a 13-month study on the ecology of malaria vectors in five villages in southern Thailand, Anopheles specimens collected on human-bait, bovid-bait, and in light traps were tested for the presence of Plasmodium vivax and P. falciparum circumsporozoite antigen by enzyme-linked immunosorbent assay. Plasmodium vivax antigen was detected in seven specimens and P. falciparum in 21 specimens, together representing 0.4% of the 7,938 specimens tested. In one village, Palao-U, circumsporozoite antigen was detected in 16 (0.7%) of the 2,196 specimens tested. In this village, combined rates of infection with P. falciparum and P. vivax were 0.6% for An. minimus, 1.1% for An. sawadwongporni, and 1.5% for An. maculatus. Circumsporozoite antigen was also detected in An. dirus, An. nivipes, An. barbirostris group, and An. hyrcanus group specimens. Combined P. falciparum and P. vivax entomologic inoculation rates in the wet season (March-October) were 0.05 for An. minimus, An. maculatus, and An. dirus, but 0 for An. sawadwongporni. Rates were higher in the dry season (November-February): 0.26 for An. minimus, 0.13 for An. maculatus, 0.13 for An. sawadwongporni, and 0 for An. dirus. The vectorial capacity, calculated based on human biting rate and rate of survival, of An. minimus during the dry season was more than two-fold higher than that of An. maculatus, the species with the second highest vectorial capacity.

Japanese encephalitis virus-specific proliferative responses of human peripheral blood T lymphocytes.

The T lymphocytes play an important role in prevention and recovery from viral infections. To characterize T lymphocyte responses to Japanese encephalitis (JE) virus infections, we analyzed JE virus-specific T lymphocytes in peripheral blood mononuclear cells (PBMC) obtained from seven JE patients and 10 vaccinees who had received a formalin-inactivated, purified JE virus vaccine (Biken vaccine). These PBMC were examined for proliferative responses against live JE virus, a glutaraldehyde-fixed lysate of cells infected with JE virus, and extracellular particles (EPs; subviral membrane vesicles released from cells infected with recombinant vaccinia viruses encoding the JE virus premembrane and envelope proteins). Japanese encephalitis virus-specific T cell proliferation was demonstrated with PBMC from both patients and vaccinees after stimulation with infectious JE virus or the lysate of JE virus-infected cells. Proliferating PBMC included CD4+ T lymphocytes and CD8+ T lymphocytes in responses to either form of JE viral antigens. Responses to EPs were observed only with PBMC from some American vaccinees whose PBMC also responded to the virus and lysate. These results indicate that JE virus infection and immunization with an inactivated JE vaccine induce JE virus-specific CD4+ and CD8+ T memory lymphocytes that can be induced to proliferate by infectious JE virus and noninfectious JE antigens.

Rapid enzyme-linked immunosorbent assay of whole blood for detection of antibodies to Japanese encephalitis virus.

The application of the rapid system of enzyme-linked immunosorbent assay (ELISA) was studied to quantify antibodies to Japanese encephalitis virus in large-scale epidemiological surveys, especially by testing under field conditions. The assay system, with 15 min for the first reaction and 30 min each for the second and the third reactions, was highly reproducible (coefficients of variation with swine positive sera were less than 5.8%) and was significantly correlated with the routine assay system with 1 h for each reaction (correlation coefficient was 0.960). Compared with the haemagglutination inhibition test, the rapid system gave a correlation coefficient of 0.916 and qualitative agreement of 96.1%. The substitution of whole blood for serum in the first reaction was also examined not only to avoid serum separation but also to apply this system to antibody quantification in animals from which sufficient amounts of sera cannot be easily obtained: only 2 microliters were needed for the test. The results obtained with 51-fold diluted whole blood had a linear relationship to those obtained with 100-fold diluted sera in swine and humans.

Detection of chikungunya virus antigen in Aedes albopictus mosquitoes by enzyme-linked immunosorbent assay.

Double-antibody sandwich and modified sandwich systems of enzyme-linked immunosorbent assay for detecting chikungunya virus antigen present in female mosquitoes, Aedes albopictus (Oahu strain), were evaluated as simple and rapid methods of selection of a highly susceptible mosquito line. Both assays were capable of detecting 3.9 X 10(1) ng (4.0 X 10(6) PFU) or more of the purified antigen. An inhibition system was less sensitive, and a direct system with adsorption of test specimens on the solid phase was not useful. Positive reactions were observed in 16 (48.5%) of 33 infected mosquitoes with with 10(6) to 10(7) PFU, which correspond to the highly susceptible group of this strain. Mosquitoes with less than 10(6) PFU were all negative, indicating the usefulness of the sandwich techniques for identifying high-titered mosquitoes.

Evaluation of enzyme-linked immunosorbent assay for quantitation of antibodies to Japanese encephalitis virus in swine sera.

Enzyme-linked immunosorbent assay (ELISA) was evaluated for the quantitation of antibodies to Japanese encephalitis virus in swine sera. The assay was highly reproducible (coefficient of variation of the absorbance values obtained with positive sera was less than 3.4%) and was significantly correlated with the conventional haemagglutination inhibition (HI) test (correlation coefficient was 0.944). The statistical analysis based on the frequency distribution of the absorbance values for 366 swine serum samples gave 0.204 as a feasible borderline to differentiate positive sera from negative sera. Using this criterion, all of the sera positive for HI antibody were found positive for antibody by ELISA and also all negative sera by ELISA were negative by HI. Inconsistent results were found in only six cases (1.6%).

Size of blood meals of Aedes albopictus and Culex tritaeniorhynchus (Diptera: Culicidae) feeding on an unrestrained dog infected with Dirofilaria immitis (Spirurida: Filariidae).

Blood meal volume was determined for two species of mosquitoes, Aedes albopictus (Skuse) and Culex tritaeniorhynchus Giles, recently demonstrated to be natural vectors of canine heartworm in Japan. When fed on unrestrained dogs, volumes were from 1 nl to 6 microliters in both species, but percentages of engorged mosquitoes were 45.2-64.3% for Ae. albopictus and 11.9-22.2% for Cx. tritaeniorhynchus. Ae. albopictus preferred to feed on human bait versus canine bait when both were exposed concurrently.

Yearly change in antibody level to Dirofilaria immitis (Spirurida: Filariidae) among humans exposed naturally to infected mosquitoes.

The IgG antibody level to Dirofilaria immitis (Leidy) increased significantly in 10.0% of 558 paired sera collected yearly from inhabitants in Miki City, Japan, indicating that they were exposed to infected mosquito bites. An additional 15.2% of paired sera showed decreases in IgG level. The binominal distribution of ELISA antibody levels among paired sera suggested an equilibrium between continued infection and antibody decreases after infection.

Distribution of immunoglobulin G and E antibody levels to salivary gland extracts of Aedes albopictus (Diptera: Culicidae) in several age groups of a Japanese population.

A total of 300 Japanese people from 2 wk to 98 yr of age were tested for immunoglobulin (Ig) G and E antibodies to salivary gland extracts of Aedes albopictus (Skuse) mosquitoes by an enzyme-linked immunosorbent assay. Almost all had IgG antibodies. The mean IgG antibody levels increased with age up to 2 yr and then leveled off, indicating a relatively frequent exposure to Aedes-mosquito bites. Distribution patterns of IgE antibody levels were similar among all age groups. The antibody status involved in mosquito allergy, especially in the five-stage sequence of skin reactivity, is discussed.

Enzyme-linked immunosorbent assay to detect antigens of Dirofilaria immitis (Spirunida: Filariidae) larvae in Aedes albopictus and Culex tritaeniorhynchus (Diptera: Culicidae).

An enzyme-linked immunosorbent assay (ELISA) method was developed for detecting the larval antigens of Dirofilaria immitis (Leidy) in Aedes albopictus (Skuse) and Culex tritaeniorhynchus Giles to replace the conventional dissection method. The assay was sensitive enough to detect 21.3 ng/ml (2.13 ng per microplate well) or more of the soluble antigen obtained from adult worms and an antigen amount corresponding to at least one larva at any developing stage. No inhibitory effect of host tissues was observed on the ELISA reaction even when the homogenate of 20 mosquitoes was included in the 1-ml ELISA diluent. Moreover, third-stage larval antigen could be detected readily when mixed with up to 100 mosquito heads. The ELISA method has been effective in field surveys of mosquito populations with low filarial infection rates.

Culex tritaeniorhynchus and Aedes albopictus (Diptera: Culicidae) as natural vectors of Dirofilaria immitis (Spirurida: Filariidae) in Miki City, Japan.

Natural infections with Dirofilaria immitis (Leidy) in a population of mosquitoes and dogs and its antibodies in a human population were surveyed in Miki City, a rural area of Japan, to reveal ecological features of this arthropod-borne zoönotic parasite. Microfilaremic and amicrofilaremic infection rates in 190 dogs were 52.6 and 9.0%, respectively, as determined by the hematocrit centrifuge method and the indirect fluorescent antibody test. An enzyme-linked immunosorbent assay (ELISA) test for antibodies to D. immitis showed that almost all of 917 inhabitants had antibodies in varying degrees, indicating frequent exposure of this parasite to the human population. Among the six species of wild mosquitoes sampled from 1985 through 1987 by attraction with dry ice, Culex tritaeniorhynchus Giles was the most abundant in two sites and Aedes albopictus (Skuse) in another two sites. Filarial infections were found every year in Cx. tritaeniorhynchus and Ae. albopictus collected between July and September, as examined by ELISA for detecting larval antigens in mosquito homogenate, suggesting that these species are important natural vectors in this survey area.

Susceptibility of Aedes albopictus and Culex tritaeniorhynchus (Diptera: Culicidae) collected in Miki City, Japan, to Dirofilaria immitis (Spirurida: Filariidae).

Female Aedes albopictus (Skuse) and Culex tritaeniorhynchus Giles from Miki City, Japan, were examined for susceptibility to infection by Dirofilaria immitis. Third-stage larvae were detected from day 7 in 10-40% of Ae. albopictus and from day 10 in 20-60% of Cx. tritaeniorhynchus, irrespective of microfilarial intake, which varied from 500 to 15,000 microfilariae per ml. The number of third-stage larvae in the labium usually varied from one to three per mosquito up to day 21, confirming the ability of these mosquitoes to transmit D. immitis.

Enzyme-linked immunosorbent assay for quantifying antigens of Dermatophagoides farinae and D. pteronyssinus (Acari: Pyroglyphidae) in house dust samples.

Double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody as capture and detector antibodies was developed for quantifying antigens of Dermatophagoides farinae Hughes and D. pteronyssinus (Trouessart) mites contained in house dust samples. This monoclonal antibody was directed against mite antigens that were also reactive to immunoglobulin E antibody in all of 10 serum samples obtained from patients allergic to mites. Histological study using fluorescent antibody revealed that the monoclonal antibody was bound to the major part of the D. farinae mite body section including fecal matter and cuticles. The detection limit of the assay system was 0.17 microgram of soluble antigens of both mite species and the antigen amount corresponding to 0.5 mites per microplate well, whether in live or dead mites. This system did not react to antigens of Tyrophagus putrescentiae (Schrank) and Cheyletus malaccensis Oudemans. Slight inhibition of less than or equal to 21.3% was observed with nonspecific substances contained in house dust, such as wool, cotton, human dander, human hair, soil, and biscuit, but no direct ELISA reactions were obtained with any of these materials. In 49 house dust samples, ELISA was significantly correlated with the conventional microscopic observation method.

Antigen levels of Dermatophagoides mites (Acari: Pyroglyphidae) in dust samples collected in homes of allergic patients.

A medical service system for testing antigen levels of Dermatophagoides farinae Hughes and D. pteronyssinus (Trouessart) mites in house dust was established to allow physicians to monitor the environment of patients with allergies. Dust samples were collected from a 1-m2 area at different sites for 1 min using a commercial collection apparatus attached to a vacuum cleaner. Extracts from fine dust fractions were processed quantitatively for antigen by a sandwich enzyme-linked immunosorbent assay. Mean antigen levels contained in samples from carpets, tatamis, and futons ranged from 431 to 852 micrograms per unit weight of dust (g). When data were expressed as micrograms per m2, the mean antigen level obtained from carpets (41 micrograms/m2) was significantly higher than that obtained from tatamis (15 micrograms/m2) and futons (14 micrograms/m2). Comparison of 37 paired samples collected from 10 homes at an interval of 1 to 2 mo indicated that high antigen levels of > 50 micrograms/m2 at four sites (three carpets and one tatami) decreased sharply after improvement of hygienic conditions surrounding allergic patients.

Analysis of enzyme-linked immunosorbent assay data for antigen quantitation using Lotus 1-2-3 software on a personal computer.

Absorbance data obtained in double-antibody sandwich enzyme-linked immunosorbent assay tests for quantitation of antigens are analyzed by a personal computer using the Lotus 1-2-3 software package. The sigmoid standard curve is processed by an iterative weighted regression analysis in the logit-log domain to obtain a linear dose-response relationship. A macro program is developed for quick calculation with easy operation, which is suited for routine laboratory tests in biomedical fields.

Prevalence of antibody to Toxoplasma gondii in Hyogo Prefecture, Japan: comparison at a 10-year interval.

We have previously surveyed antibody to Toxoplasma gondii among Japanese populations. In this report, we studied the current situation of antibody prevalence and compared it with the situation approximately 10 years before. A total of 1,800 human serum samples were collected at the Central Laboratory of Kobe University Hospital from June through September, 1995, and were examined for Toxoplasma antibody using enzyme-linked immunosorbent assay. The overall prevalence was found to be 16.4% with similar seropositivities in males (16.8%) and females (15.9%). Prevalence of antibody increased with age, reaching 41.0% in males and 59.0% in females at 80 years or more. Comparison with data obtained at the same hospital in 1981 to 1982 indicated that seropositivities at 30-39 years significantly decreased in both males and females. A positivity currently obtained at a certain age group was similar to a positivity previously obtained at the corresponding age group (10 years younger), indicating that the previous age prevalence curve shifted to the current position. A serological survey among stray cats collected in Hyogo Prefecture in 1990-1991 indicated that 44 (19.0%) of 231 cats were positive for Toxoplasma antibody as determined by the latex agglutination test. These results suggested less transmission of Toxoplasma to humans in Hyogo Prefecture at least for the last 10 years comparing with the situation in the past, although the transmission cycle among cats was still active in nature.